Despite the prevalence of hperactivity in school-age children, few attempts have been made to identify or treat this disorder prior to school entrance. Parent reports, however, suggest that in most cases hyperactivity and associated impulsivity and disciplinary problems are present in some form from infancy or toddlerhood onward. Follow-up studies of preschool and school-age hypezactive children further suggest that this disorder persists and is relatively resistant to treatment. Thus, the present research is aimed at the early identification and treatment of childhood hyperactivity. Hyperactive toddlers (2 1/2 - 3 1/2) are being compared with matched controls on a variety of parent report, family history, behavioral, and cognitive measures to determine the correlates of hypezactivity in toddlers and the usefulness of certain assessment devices with this age group. The efficiency of parent training groups as a treatment strategy is then being evaluated. Therapeutic effect is being assessed at the conclusion of eight weeks of structured group intervention and in a six-month post-treatment follow-up to evaluate short-term gains and maintence of change in both child behavior and parenting skills.